Governor



A. KALIN Nov. 2 1943,

GOVERNOR Filed Aug. 5, '1940 zsheetsfheet 1 INVENTOR. KA -,5 6 I? 7' K44 /A/ Patented Nov. 2,:1943.

covaaNoa.

Albert Kalin, Oleveland, om

a pn amnnumz s, 1940, Serial No. 350.255

12 Claims.

This application and my application SerialNoi 350,254, filedAugust 3, 1940; Patent 2,219,229 issued October 22, 1940, are companion. applications relatingto governors for regulating prime movers and other machines andapparatus. Reference is directed 'to the above identified patent for a: more comprehensive discussion than given herein or problems relating to the making and operating of governors of. the typeherein' shown.

The objects of the present invention are gen-- erally the same as thoseof the companion appll cation; The objects include the improvement oi governor mechanisms in respectlto increasing responsiveness on part. or. the mechanisms to changes in conditions or thegoverned-imachines: or apparatusrequiring governing operations-to I be en'ectedand in respect-to securing greater aim plicity in governor construction together with greater accuracy of operation overlong periodsof' time on part of the governors so constructed;

A specific object is to provide certainmodiflcations or the means showninthe companionappllcation for securing. primary and* secondary compensation in governors; and particularly isochronous governors.

Other objects oi the invention will be-brought out in connection with thefollowing description or the illustrative embodiments shown :herewith.

In the drawings, Fig. 1 is a vertical sectional view centrally cuttingthe main operating parts 01' the governor; Fig. 21s a relatively enlarged detail vertical. sectional: view taken along the line 2-2 onFig. 1: Fi-gs..3 and 4 are detailvertical sectional views showing modified constructions as though taken'along the line 2-4 on a" governor similar to that oixFig. 1; Fig. 5 is a de-. tail view taken along a plane such as that 011F182 1 and showing amodiflcation similartothat of Fig. 4 but associated withthe lower end-oi' al pilotvalve plunger and receivingcompensationpiston unit; Fig. 6 is a detail sectional view taken=similarly to Fig. .5 showing still another modification; Fig. '7 is a relatively enlarged sectional detail'view taken in a plane similar to that of Fig. 1 in which a compensating fluid duct is further-modified. and Fig. 8 is. a generalassembly verticalsectional view a (mainly diagrammatical) showing still an other-modification.

Governors of the typeshown---adapted for speed regulation of prime movers and-other machinery-have, as the primary weighing elementr a fly-ball mechanism such as shown at W, Figs.

1 and8, rotatably mounted-and connected with a rotary part of the machine to be governed.

The condition of the flyball mechanism varies acorder to'preventv over-correction. This is'done cording to. the *speed of. the rotary part; This variation canbeutilized effectively through the agency of'ahydraulic relaysystem. including a single -or double acting hydraulic servo-motor anda pilot valve connected with the fly--ball mechanism: to "control the flow of hydraulic 1 fluid toaand 'ironr thex servo-motor,v whereby to: regulate-the rate oi flow oi: energy medium to the prime mover. Such mechanism and'relay together -with:compensating. means acting as will be further explained belowsservesto maintain substantially constant speedof such prime mover notwithstanding variations: in load imposedthereon. The-pilot valve usually'includes a valve plunger adapted. to move axially in: a-

cooperating valve partflor instance a sleeve with lateral .ports.

. The pilot valveplunger of. the hydraulic'relay, in present dayxisochronous governors arranged to operate as above outlined, is ordinarily maintainedtduringthe operation oi the-governor in a state or rotation relative to the: coacting. valve element-,thereby toreduce statie' friction as more fully explainedin the companion application,

facilitating; axial movement, of the plunger when regulation-initiating impulses are impartedthereto by the weighing: element. After the servo-motor startsits movement in the necessary direction to eflect'regulationofthegoverned-ma-- chine it is necessary to check said movement in by primary compensating means which may operate on the pilot valve plunger as ai'unction of servo-motor movement either to restrain theaxia'l movement 01' the pilot valve plunger or in some other mannerto counteract its axial movement; Then, because the weighing-.elementupon proper correction being efle'cted willi'eventually returnto a predeterminedpositiomanother compensatgngaction islnecessaryin order to prevent-a .per-

manent change inspeed. This other compensating action, in isochronous governors; is referred to assecondary compensation. In'governor having hydraulic power. relays ior. regulation, primary and secondary compensation can be effectedvery simply byhydraulic means including, in effect, a'hydraulic lever the operation or whichis similar to a mechanical lever with a movable iul crum such as well knownin the art. The isochronous govemorarrangements priorto the disclosures hereof and *those oirthe companion application above identified were subject. to-static. friction inthe relative'movement of parts necessary for eflecting primary and secondary compensation. My arrangements arenot; in other n ""the'latter. The sleeve 30 is appropriately fixed or reduced portion24 words the operations necessary for effecting pritogether by fluid tight joints so as toretain the hydraulic fluid.

A shaft extends through the base and can be appropriately coupled with a turning part of the mechanism to be governed as by splines 5a inside the shaft. The upper end of the. shaft 5 has a gear I thereon functioning as one element of a gear pump and an element of a gear train for driving the ball-head or weighing element Gear l2 on a sleeve portion l3 of a ball-head casting II is part or the gear train. The elements'of the pump, gear drive, sump, etc. not shown herein are fully illustrated inmy said Patent 2,219,229. e

fThe ball- -head assembly may comprise any suitable arrangement of centrifugally operated members such as weighted bell-cranks 40 pivoted as at 42 on the ball-head casting. and ,-havingball-arrn fingers 44, which are adapted to ,adjust the vertical position of a pilot valve plunger '20 which, as shown, operates inside a fixed valve sleeve 30 mounted in the power case a,,bor el 8 of a central tubular portion l5 of l rigidly in place in the bore l3.

Int-he particular arrangement shown the pilot valve plungerturns with the ball-head whenever the latter is turned. The plunger may instead .be held stationary while the valve; sleeve is turned, forinstance as illustrated in said patent, Fig. 6 thereofi The'ball-armflngers extend into contact .with a ball-'flnger thrust member 45 which is secured to the upper reduced end of the pilot ,valve' plunger as by means of a nut 46which ing 41 and upwardly iacing- 'shoulder on the valve plunger. The ball-arm fingers may have their inner .ends

, seated in shallow downwardly racing depressions ,.seat collar 49 which contains the outer race rin of the bearing 41, the arrangement permitting the pilot valve to turn freely while the spring seat collar and speeder spring remain stationary.

, The force of the speeder spring may be adjusted by the usual means, not shown.

Thepilot valve plunger 20 is designed to slide pulses imparted by the fly-balls and speeder springasisusual and well understood in the art.

' ,Th'e plunger has lands 2|", 25 and 26 all slidably fitting the bore 33. The

lands '25 and 26 function as'plugs to cover and uncover lateral ports 35 and 36 in the sleeve 30. A relatively long neck of the plunger separates the landsv 25 and 25and the open space so steady-state running condition 01 the governor. I

both sets of ports 35 and 38 being closed. A receiving or actuated compensation piston is shown at 50, slidably arranged in a cylindrical downward extension of the bore 33 of the sleeve 30. The receiving compensation piston of. Fig. 1, which may be made as part of the valve plunger 20, could be the same'for the modifications of Figs. 3 to '7. The neck 21 on the plunger which separates land from. the piston 50 afiords a space between it and the adjacent wall of the sleeve which is constantly vented to a low pressure area 1-. e. sump, as through lateral open- .ings 31 in the sleeve. This effectually prevents pressure from above the land 25 from being communicated to the compensation duct, which latter terminates, at one end, at the lower face of j clamps an inner bearing race ring of a ball bearthe thrust member against an 1 main part of the sump the piston 50.

The hydraulic system, as partly described above, includes a sump provided in the space 7 generally surrounding the portion l5 of the power case; and various chamber and duct portions of the apparatus which communicate freely with the sump are marked S, SI, S2, etc. The gear pump'is supplied with hydraulic fluid from a as at SI. The pump, as shown in my said patent, discharges fluid past suitable check valves into the space marked Pl which is in open communication with a spring loaded accumulator (not shown) through ducts '66, 61 and 68.

fluid passing to the sump through a duct 12 past a space S2 surrounding the sleeve 30 at ports 36. The ports 36 and the lateral openings 31 between the valve plunger and the receiving compensation piston 50 are always in open communication with the sump.

The servo-motor cylinder block 3 is'bored on three diameters from its lower end as at 15, 16 and 18. The bore 15 is the main power cylinder bore in which is slidably carried a power piston 80. The servo-motor, as shown, is double acting. A tubular upward extension 8| of the piston slidably closes the upper end of the power cylinder at the bore 16. The extension 8| of the piston is centrally bored from its top side as at 82 to form a primary or actuating compensation cylinder for an actuating compensation I piston 83 which is fixed solidly in the bore 18 against a shoulder formed by a counterbore 19 upwardly beyond the bore 18'. The actuating compensating piston is hollow for its full length at 84 to form part of a delivery duct for compensation fluid extending from the space marked C (as will be shown) to the lower end of the receiving compensation V "easily in the bore 33 of the sleeve 30 under im- I sure space Pl (around sleeve 30) to the upper afiorded communicates with lateral openings 34- The plunger is illusthe part of the power cylinder 15 through a passage 69 formed partly in a bridge portion 90 of the power case 2 thus subjecting the top Side of the piston to constant pressure at all times.

Actuation of the piston 80 results. in part, from the release of fluid from the constant pressure system (from Pl) through {1e space between the pilot valve lands 25 and 25 and surrounding prime mover governed by the mechanism. Downward movement of the power piston (slowing down of such prime mover) results from an upward movement of the pilot valve plunger and consequent release of regulating fluid from RI .and R, such movement of the ,pilot valve plunger opening ports 36 in the sleeve 30 and releasing regulating'oil from R. into the sump at S2. The cylinder space S4 above the piston extension 8 l is open to a negligible pressure area through passage 92 leading into the speeder case 4 as indicated on Fig. 1. I I

Appropriate additional ducts for transfer of "fluid between the pilot valve" spaces mentioned and the power cylinder block spaces include a horizontal regulation fluid duct 94 leading from the space R to a duct 95 formed partly as a channel in the attaching face of the block 3,

the lower end of which duct 95 opens into the space RI below the piston 80. Compensation fluiddischarged from the tubular actuating compensation piston 83 goes to a diagonally extending-passage 98 in the upper end of the power cylinder block (partly in the wall of the tube 83 as shown), then to a cross channel 99 in the block 3, then down a vertical channel I to a bore lill in another bridge portion of the power case, and finally to an enlargedcavity I03 surrounding the lower end of thevalve sleeve 33 and communicating freely with the lower end of the receiving compensation piston cylinder (space An adjustable secondary compensation pressure-equalizing by-pass in the ocompensation fluid duct just described (between said duct and a negligible pressure area) is shown at C2, comprising a threaded needle valve pin H0 in an upper part of the block 3 and having a conical end projecting into the bore 84 of the piston 83,

leaving a small gap between said conical end and the bore. Lateral openings I I2 communicate with an enlarged space around the needle valve pin and permit free flow of fluid between the compensation fluid duct and a permanently maintained fluid reservoir space S6 in the speeder case.

Primary compensation; in the arrangement according to Figs. 1 to 7, is effected by providing for two way acting yieldability in the compensation duct, producing restraint on the Pilot valve plunger movement as will now be described. Referring first to Figs. 1 and 2:

Leading upwardly from a suitable portion of the compensation duct is a chamber C3 arranged to'contain an elastic compressible medium (e. g. air or other gas, such as may be released from the hydraulic fluid) which medium operates through the fluid in the compensation duct: (11) to oppose or place restraint on the upward movement of the pilot valve plunger 20 (acting on the receiving compensation piston 50) when the fly-ball mechanism lifts the plunger; and (b) to oppose or place restraint on the downward reduces pressure below normal in the compensation fluid duct; and, because of the elastic expansible nature of the fluid in the upper part of the chamber C3, the eflect oi the reduced pressure is todraw downwardly yieldably on the lower face of the receiving compensation piston movement of the plunger when the fly-ball mech- (function (1). Similarly, compressionoi the elastic fluid'in C3 results in upward yielding force being transmitted to the valve plunger when the servo-motor piston is raised (function 12). The chamber C3.can be made adjustable to vary the elastic fluid content thereot. The lower part of the chamberas shown is formed by a threaded hole H5 in the block 3 communicating with the compensation duct,po1:tion98, and the upper'partby an inverted cup member lliiclosed at. the "top and peripherally threaded so as nicely to flt the threads 01 the hole H5,

sealing the chamber at the threads partly through the agency of the hydraulic operating fluid maintained in the reservoir S6. Part of the chamber may be occupiedby a fixed post I I8 which extends upwardlyfrom the block 3 well above the level at which hydraulic compensation fluid is maintained in the chamber. 'Said. level would ordinarily be maintained about even. with the lower rim of the cap member, since if more than just sufllcient air or gas tends to occup the chamber than can be contained by the cap at normal pressure it will eventually escape by way of the threaded connection between the cap and hole H5; In any event (for instance should the adjustment feature be omitted) the excess air or gas will eventually leave the chamber byway of the duct portion 98 and the adjustable secondary compensation bleederjC2. ,7

Operation.Assuming that the shaft is, connected to a prime mover running at constant speed (normal, as determined by speed setting through the speeder spring 48) the fly-ball mechanism maintains the pilot valve plunger. centered so long as that condition obtains (steady state). It a certain percentage of the load on the prime mover v is dissipated, then the speed increases proportionately, and thefpilot valve plunger will be raised by outward movement of the 'fly-ball weights, thus opening the ports 36 and permitting the discharge of regulation fluid from R to the sump. Arrows on the parts indicate the direction of movement of the parts and hydraulic fluid in case of decrease in load and resulting increase in speed. Constant pressure at P2 then lowers the power piston of the servo-motor, reducing the prime mover speed through the stem 81 and connected mechanism. Eventually this action of the servo-motor would be checked by return movement of the fly-balls toward original thereof. A negligible volume.v of hydraulic fluid moves inwardly through the secondarycompensation by-pass C2 during this action. The restraining action (primary compensation) on the plunger, although exerting only a small percentage of the force exerted thereon by the speeded fly-balls, augments the, force of the speeder spring 48 the necessary amount to cause the fly-balls to return sufllciently quickly to a very slight speed changes ball mechanism. As

36 so that an underdoes not take air or gas in the chamber C3, or equivalent elastic means hereinafter described, the column oi! hydraulic fluid in the compensation fluid duct 98-IOI is also elastic in its effect on the receiving compensation piston 50, and, consequently the valve plunger is free to move in response to imposed on the hythe prime mover, under the correcting influence of the servo-motor, returns toward normal speed, it is necessary to remove the restraining influence of the vacuum in the chamber C3 on the piston 50 and thevalve plunger in unison with the return to normal speed on'part of the prime mover, for otherwise a reverse'action oi the pilot valve would take place, at least temporarily, such as when speed acceleration is needed. In other words isochronous governing would not be accomplished. Secondary compensation, necessary for isochronous governing, is accomplished by by-passing fluid from the sump reservoir S6 into the compensation 'duct thus gradually relieving the suction force generated by the partial vacuum in the chamber C3. The gas in C3, in returning to normal pressure, finally establishes a neutral or non-acting pressure condition in the compensation duct. The leakage through the secondarycompensation by-pass C2 is regulated in accordance with the ability of the governed machine to respond to corrective impulses by the servo-motor; and once the needle valve H3 has been adjusted to suit the machine on which the governor is installed or with which connected,

,it needs no further attention.

When load on the prime mover is increased over normal and its speed thereby decreases, the action of the governor is the reverse of that just described. The pilot valve plunger is then pressed 'down by the speeder spring as the flyball weights move inwardly. This opens the ports 35 to the interior of the sleeve 30 and sub- Jects'the lower side of the piston 80 to sufllcient pressure to lift it, the fluid moving from PI through ports 35 and 34, space R, ducts 94, etc. to RI. The actuating compensation piston 83 then pumps fluid into the compensation duct, compressing the air or gas trapped in the chamber C3 thus elastically pressing upwardly on the receiving compensation piston 50 and the pilot valve plunger, restraining the downward movement of the latter and tending to decrease the efiective force of the speeder spring in opposing outward movement of the fly-balls. As the pilot valve plunger returns to normal position upon initiating the speed-corrective cycle, the compressed air or gas expands to unstressed condition, forcing fluid from the compensation duct at the by-pass C2 and ports II2. Were it not for the yield in the compensation duct provided as by the gas pocket inthe space C3, the pilot valve plunger would be locked against being moved quickly either downwardly or'upwardly .by the fly-balls in response to speed change.

Therefore the governor would not respond to a axially, with no possibility oi sticking due to accumulation of ioreignmatter (as from the oil) in the microscopically small clearance spaces between the sliding guides; and, by reason, of the elasticity in the compensation fluid duct the valve plunger cannot become oil locked by hydraulic fluid in said duct. Immediate responsive operation of the governor to influences calling for changes in a condition of the governed machine or mechanism'is thus assured.

The primary weighing element can be made responsive to any force factors other than speed, for instance, fluid or current pressure or flow, gravity, etc. I

Referring to Fig. 3, this illustrates another means of effecting primary compensation by restraining the valving movement of the pilot valve through the agency of the hydraulic coupling between the servo-motor and the receiving compensation piston 50. As shown a cylinder I2Il is connected at one end, as at I2I, with the compensation duct, as at the portion 98 thereof. Slidable in the cylinder is a piston I22 which is normally held as in the position shown by a spring I23 connected at one end to the piston and at the other to afixed part such as a threaded block I24 in the outer end of the bore'whlch forms the cylinder. The outer end of the cylin der, as shown, is vented through the block as at I25. The spring I23, during steady state conditions of the governed machine or apparatus, is in a'neutral or non-stressed condition. When the pilot valve plunger is moved downwardly the receiving compensation piston acting through the column of fluid in the compensation duct, com presses the spring I23 and when the plunger moves upwardly the spring I23 is stretched. The restraint placed on the pilot valve plunger is removed when normal pressure is reestablished in the conipensation fluid duct by the adjustable bleeder, at C2.

The arrangement of Fig. 4 is in a sense a combination of the Fig. 2 and Fig. 3 devices. An upstanding bellows I30 with resilient wall portions is in sealed relation to the compensation fluid duct as at I3I. The longitudinal resiliency of the bellows, yieldingly resisting axial collapse and expansion of its corrugated side wall, acts to augment the resistance to contraction and expansion of the pocket of air or gas trapped in the upper portion of the bellows. The operation will be obvious from the preceding description.

Fig. 5 shows a bellows I33 similar to that of Fig. 4 is connected at its open end to the compensation fluid duct and in inverted position relative to'the bellows of Fig. 4. The bellows.

the receiving compensation cylinder as before,

but through a wall of the sleeve 30 (see openings I34) above the lower end of the sleeve 30. No air or gas will be trapped in the bellows of Fig. 5 but the yielding resistance to longitudinal expansion and contraction on part of the bellows change in speed until fluid had leaked in or out p 'at the by-pass C2.

- By reason of the constant relative rotation {maintained between both the pilot valve plunger and receiving compensating piston and their guide bores during the entire operation of the that said plunger and I33 causes the latter to eiiect primary compensationacting through the hydraulic fluid medium on the receiving compensation piston 50 in a manner similarly to the action of the device of Fig. 3. The space surrounding the bellows I33 is vented as to the sump at I35.

Fig. 6 shows an adaptation of the arrangement nf'l igj but in which the spring-positioned piston (corresponding to piston in of Fig. 3) isv turned relative to its cylinder at all times, whereby to eliminate any possibility of the piston sticking" i. e. refusing to move axially during regulation operations of the governor. As shown A the piston I40 operates in the lower end of the sleeve 30, beyond the point oi communication of the compensation fluid duct portion IOI there- .with, A stub shaft I42 extends upwardly from the gear supporting pwtion oi! the shaft 5 through a close fitting hole I43 in a plug I43 which lies above the gear I and separates the pump chamber from the space at the lower end of the sleeve 30. The piston I40 and shaft I42 are connected by a coil spring I44, shown with its ends threaded onto the shaft and piston respectively. The cylinder space I45 below the piston I 40 is vented to the sump as at I46. Normally the spring I44 is unstressed axially. The device except for the relative rotation of the piston I40 and its cylinder wall is essentially the equivalent of the Fig. 5 arrangement.

Fig. 7 illustrates an arrangement that could be used instead of the compensation fluid retaining but elastically resisted primary compensation devices of Figs. 1 to 6. This comprises a pair of oppositely acting spring closed check valves associated with the hydraulic coupling (e. g.) between the actuating compensation piston 83 and the receiving compensation piston 50. The device can be incorporation in one of the compensation fluid duct portions which are formed between the adjacent faces 01 the power case 2 and power cylinder block 3, as in the duct portion I00. As shown a valve disc I50 is seated by a spring I5I over a plate I52 with apertures I53 leading from the duct I to the sump past the valve disc. A reversely acting valve disc I55 is seated by a spring I56 against the" end face oi! an enlarged laterai'extensio'n I51 01 the compensation fluid duct I00.- Said end faceis apertured as at I58 and the apertures communicate suitably with the sump as through a duct I59. The springs I| and I56 exert equal force on their respective discs. v

In operation (Fig. 7) the spring pressed discs open to allow the passage or fluid into and out of the compensation fluid duct so that the weighing-element-actuated movement of the pilot valve plunger is resisted by the pumping action of the actuating compensation piston and cylinder couple 8I83, but the resistance is limited at all times by the force of the springs I5I or I56 (whichever is rendered active, as determined by the direction of relative movement 01 the elements 01 said couple 8I83). The device permits by-pass of fluid into or out 01 the compensation duct as required in order to permit the weighing element to act quickly on the pilot valve plunger in the event of a quick load change. Irrespective of the direction of movement of the actuating compensation piston and cylinder by the servo-motor, said actuating piston and cylinder maintains a restraining forceon the pilot valve plunger limited by the loading 01 the springs. The restraint to pilot valve movement originating from fly-balls is likewise limited by the loading 01 the springs. a

' A flexible chamber (as in Fig. 5 for instance), or an equivalent thereof, may be used with thedevice of Fig. 7 in order to maintain elasticity as to fluid in .the compensation duct at all times. In such case the spring pressed discs would simply limit the elastic force irrespective or how much fluid is pumped by the actuating compensation piston.

Referring to Fig. 8 this illustrates an arrangement in which a dash-pot, the elements of which are maintained constantly in a state of relative rotation, is caused to exert compensating influence on the pilot valve of a hydraulic relay in response to regulating'operations on part of the servo-motor of the relay. Secondary compen- 10 associated with the dash-pot.

The hydraulic relay is the same in principle as that of Fig. lhence it will not be described in detail. The parts corresponding to those of Fig. 1 are numbered similarly. For convenience the servo-motor is shown in inverted position relative to the servo-motor of Fig. 1.

The servo-motor piston 80 operates in a downward direction to increase speed (assuming connection with a prime mover) whenever the weighing element W, as by inward movement or the fly-balls, allows the speeder spring to depress the plunger 20. Reverse movements of the parts and fluid (those movements indicated by the arrows) occur. upon outward movement 0! the fly-balls. An actuating part 46', for speed adjustment, is shown bearing downwardly on the upper end of the speeder spring 48. The speeder spring and the adjusting part are made large enough to accommodate the dash pot and actuating arrangement therefor. The dash-pot, as shown, is a cylinder-forming cup I00 attached as at IGI to the upper reduced end of the pilot valve plunger and serving in place of the nut 46 of Fig. 1 as to the bearing assembly. The cup cylinder I60 thus rotates with the pilot valve plunger. I a

A piston I63 in the dash-pot cylinder is held normally in a position such as that shown by a spring I64 fixedly connected at its upper end with an adjusting lever I65 which latter has a fixed pivot at I66. The left hand end of the lever is connected to a link or rod I6I'and the lower end of the link or rod is connected with the servo-motor piston 80. The adjustable leakofl may be a threaded needle valve I68 on the dash-pot piston.

When the valve plunger is depressed by the speeder spring (fly-balls moving inwardly) the resulting downward movement of the servo-motor piston acts through the link and lever to stretch the spring I64 which then, through the piston I63 tends to evacuate the dash-pot cylinder space below the piston. This restrains the downward movement of the pilot valve plunger and, finally, the restraining influence is removed by the secondary compensation leak-oi! device A reverse action takes place (that indicated by the arrows) when the valve plunger 20 is raised by the overspeeded fly-balls, and in such event the fluid mediumin the lower part of the dash-pot is subjected to positive pressure by the compression of the spring I64 incident to upward movement of the servo-motor piston.

1. A governor having a primary weighing ele- .ment connected to a pilot valve plunger which is reciprocably mounted relative to a cooperating pilot valve element whereby theweighing element and plunger can initiate regulation of a governed mechanism by controlling the flow of a hydraulic medium in respect to a servo-motor, and wherein the plunger and its cooperating valve element have circular valving surface con sation is accomplished by an adjustable leak-oil? tact, means to maintain the plunger and its cooperating valve element in relative unidirectional rotation during the entire operation of the means including an actuating compensation displacement unit operated by the servo=niotor, and a receiving compensation piston/ cylinder unit one governor, hydraulically acting compensation element of which is fixed relative to the plunger and the other element of which is infixed relation to said cooperating'valve element so that' fl the elements of the receiving compensation piston/cylinder unit likewise turn unidirectionally relative'toeach other during the entire opera tion of the governor, and an elastically expansible and contractable duct hydraulically coupling the actuating and receiving compensation units together in a manner yieldably'to restrain longitudinal movement imparted .to the valve plunger by the weighing element. r

2.v A governor wherein arotary weighing element acts through a pilot valveplungerwhich is rctatedcontinuously andunidirectionally in a cooperating valve sleeve by theweighing element and is moved axially by said element to initiate regulating impulses of a servo-motor, an actuating compensation displacement means operatively connected to'the servo-motor, a compensation fluid duct in which hydraulic fluid is a resilient wall said bellows constituting part of the'd-uct and extending downwardly so that only the resilient wall is effective to lend elasticity to the duct. a

8. In a governor of the type which acts to effect regulation hydraulically through a servomotor, valve 'means to controlthe servo-motor,

and a weighing element controlling the valve means, compensation means'including a hydraulic coupling including a duct for hydraulic fluid between the servo-motor and valve means so arranged that regulating movement of the servomotor'initiates compensating movement of hyj draulic fluid in the duct, said duct-havinga fixed piston inthe cylinder, and spring means norcylinder portion forminga' branch thereof, a

mally holding the piston in a predetermined posimoved by the displacement means, one end of the plunger and the valve sleeve constituting a receiving compensation piston/cylinder and one end of said fluid duct, and means cooperating with hydraulic fluid in. 'said' duct to render the same, in effect, elastic so as yieldably 'torestrain thepilot valve plunger.

3. In a governor of the type which acts to effect regulation hydraulically through a servo-motor,

, valve means to control the servo-motor, and a weighing element controlling the valve means, compensation means including a hydraulic coupling including a duct for hydraulic fluid between the servo-motor and valve means so arranged that regulating movement of the servo-motor initiates compensating movement of. hydraulic fluid in the duct, means to impart motion of the hydraulic fluid to the valve means, and means forming a retaining chamber for expansible and contractable I fluid, said chamber constituting part of the duct and operable to render the hydraulic fluid elastic in effect for resiliently biasing the valve means.

4. In a governor according to claim 3, the artion with respect to the cylinder:

normally holding the piston and cylinder against axial relative movement, and means to maintain constant relative rotation'between' the piston and cylinder. v r I 10. Anisochronous governor for primernovers subjectto varying loads, comprising: a shaft adapted to be rotated by'the prime mover, speedresponsive means driven by said shaft, a primemover-regulating servo-motor, means for supplying hydraulic fluid under pressure to said servo-motor, a plunger-type pilot valve assembly controlling said supply of hydraulic fluid to said servo-motor in accordance withprime mover speed, the pilot valve comprising two telescope ingly-related members having cylindrical surfaces in mating contact continuously unidirec rangement wherein said chamber has adjusting I means to vary its normal content.

5. In a governor according to rangement wherein said chamber hasa displacement member extending thereinto and a cup forms part of the chamber and is adjustable toward and away from the displacement member to vary the effective size of the chamber.

6. The arrangement according to claim 3 wherein the retaining chamber forming means ha'sa resilient wall capable of being expanded claim 3'th e ar-" aridfcontracted by action of the hydraulic fluid on the contained expansible and ,contractible fluid. I

'7. In a governor of the type which acts to effect regulation hydraulically through a servo-motor, valve means to control the servo-motor, and a weighing element controlling the valve means, compensation means including a hydraulic cou pling including a duct for hydraulic fluid between the servo-motor and valve means so arranged that regulating movement of the servomotor initiates compensating movement of hydraulic fluid in the duct, and a bellows having tionallyrelatively rotated by said shaft, primary compensation means for biasing said pilot valve against axial movements imparted thereto by said speed-responsive means, said pilot valve biasing means comprising a-secondfluid-pressure system independent'of said source of servo-motor-actuatin'g fluid pressure, means for varying the pressure in said second system comprising a displacement element actuated by servo-motor move-,

ment, a cylindrical piston-constituting element on the axially movable or plunger member of said pilot valve assembly in mating contact with a cylindrical surface of the other member and correspondingly continuously unidirectionally relatively rotated with respect to the contacting surface and elasticallyv yieldable reversibly acting means operatively associated with said second fluid pressure system in a manner to effect te porary retention of biasing force on the pilot valve after regulating movement of the servo-motor has been effected, and secondary compensation means comprising a metering ,leak'element in saidsecond fluid-pressure system for dissipating said biasing force. l

11. In a governor mechanism, a hydraulic relay including a regulating servo-motor and a pilot valve arranged to initiate regulating movements of the servomotor'in response to predetermined change of a condition tobe governed, said pilot valve comprising a cylindrical plunger member and complementary valving member, means for causing continuous unidirectional relative rotation between the valve members, one end of the valve plunger and an adjacent portion of the placement means and the piston of said unit to render the displaced hydraulic fluid elastic in its eflect on said piston irrespective e! the direction of movement of the servo-motor.

12. Governor mechanism according to claim 11 wherein said complementary valving member is a sleeve into which the plunger is insertable at one end 0! the sleeve, said sleeve having an inner bore portion for engagement with the pistonconstituting portion of the valve plunger, said bore portion being no larger than the valving portion of the sleeve whereby the piston and plunger can be inserted in and removed from the sleeve as a unit at said end of the sleeve.

" amm'r KALIN. 

